Thought and thinking are mental forms and processes, respectively ("thought"'s both). Thinking allows beings to model the world and to deal with it according to their objectives, plans, ends and desires. Words referring to similar concepts and processes include cognition, sentience, consciousness, idea, and imagination. Definition Representative reactions towards stimuli from internal chemical reactions or external environmental factors. The word comes from Old English . þoht, geþoht… (More on Thinking)